Brick Calculator
Enter the wall size and brick size to find how many bricks you need.
What this tool does
The number of bricks is the wall area divided by the area of one brick plus its mortar joints. A UK brick of 215 × 65 mm with 10 mm joints covers 0.016875 m², about 59 bricks per square metre, so a 5 m by 2.4 m wall needs about 711 bricks before waste and about 747 with a 5% allowance. Enter your own wall above.
Divides the net wall area by the area of one brick face including joints.
Adds a waste allowance and estimates the mortar from the wall volume.
How to use it
- Choose metres or feet and enter the wall length and height.
- Enter the area of any doors and windows to leave out.
- Choose the brick size, or enter a custom size, and the mortar joint.
- Read the bricks to order and the mortar volume.
Why use this calculator
Counts bricks from the wall size, the real brick dimensions and the mortar joint, and takes off doors and windows. Ordering too few bricks stops a job; too many wastes money. Brick sizes differ between countries, and the joints add to each brick's footprint, so a rule of thumb per square metre is not reliable without the real size.
Why we built it
We built the brick calculator to use the real brick size and joint, take off the doors and windows, and estimate the mortar. Measure the wall with the square footage calculator and plan paving with the paver calculator.
Who this tool is for
- Homeowners building garden walls and extensions
- Builders and landscapers pricing jobs
- DIY learners planning a project
When to use it
- Planning a garden wall, boundary wall or barbecue.
- Pricing a house extension.
- Checking a builder's quote.
- Estimating a school or DIY project.
How it works
Each brick covers (length + joint) × (height + joint) on the face of the wall. Bricks = net wall area ÷ that area, then multiplied by (1 + waste). Mortar volume = wall area × brick depth − the volume of the bricks themselves. A UK metric brick is 215 × 65 × 102.5 mm and a US modular brick is 7⅝ × 2¼ × 3⅝ in.
Example: a wall 5 m long and 2.4 m high is 12 m². One UK brick with 10 mm joints covers 225 × 75 = 16,875 mm², so 59.3 bricks per m². The wall needs 711.1, rounded up to 712, and 747 with a 5% allowance.
This is a planning estimate from the figures you enter. Real projects vary, so check dimensions on site and allow for waste and local rules before you buy or build.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Wall measured in | Metres |
| Wall length | 5 |
| Wall height | 2.4 |
| Area of doors and windows to leave out | 0 |
| Brick size | UK metric, 215 × 65 × 102.5 mm |
| Custom brick length | 215 |
| Custom brick height | 65 |
| Custom brick depth | 102.5 |
| Mortar joint | 10 |
| Allowance for cuts and breakage | 5 |
With those inputs, the calculator returns:
- Bricks to order: 747
- Net wall area: 12 m²
- Bricks per m² (with joints): 59.3
- Bricks before the allowance: 712
- Mortar needed (approx.): 211 litres
What you give it, and what you get back
| Item | Details |
|---|---|
| Wall size and openings | Length, height and the area of doors and windows, in metres or feet. |
| Brick and joint | A preset UK or US size, or your own dimensions, and the mortar joint in millimetres. |
| Output | Bricks to order, bricks before allowance, bricks per square metre and mortar litres. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| I need a double-skin wall | The tool counts a single skin laid lengthways. | Double the brick count for two skins. |
| My bricks are a different size | Brick sizes vary by maker and country. | Choose "Custom" and enter the real size. |
| The mortar figure seems low | It is the volume of the joints only. | Mortar mixing and waste mean you need to buy more than the volume. |
Assumptions and limitations
- Single skin, brick laid lengthways.
- No corner, bond or coursing details.
Frequently asked questions
How many bricks are in a square metre?
With standard UK bricks and 10 mm joints, about 59 for a single skin laid lengthways.
How do I work out how many bricks I need?
Divide the wall area by the area of one brick plus joints, and add an allowance for waste.
How much waste should I allow?
About 5% is common, more for complex shapes with many cuts.
Does it include doors and windows?
Enter their area and it is taken off the wall.
How much mortar do I need?
The result shows the volume of the joints. Add extra for waste and the mix you use.
Is my information sent anywhere?
No. The calculation runs in your browser and nothing leaves the page.